Rotary pump with adjustable gate



L. F. moonv.

ROTARX PUMP WITH ADJUSTABLE GATE. APPLICATION mm JUNE 10. I919.

Patented Nov. 25, 1919.

4 SHEETS-SHEET fl- L. F. MOODY.

ROTARY PUMP WIIH ADJUSTABLE GATE.

APPLICATION man JUNE 10. I919.

Patented. Nov. 25, 1919.

4 SHEETS-SHEET 2.

54 5 F iglt L. F. MOODY.

ROTARY PUMP WITH ADJUSTABLE GATE.

APPLICATION FILED JUNE 10, I919.

Patented Nov. 25, 1919.

Lz mo 4 SHEETS-SHEET 3- L. F. MUDDY.

ROTARY PUMP WITH ADJUSTABLE GATE.

APPLICATION FILED JUNE 10. 1919.

Lfi fil Q0 Patented Nov. 25, 1919.-

4 SHEETS-SHEET 4.

a' err-1 no'rnny PUMP WITH ADJUSTABLE GATE.

Specification of Letters Patent.

Patented Nov. 25, 1919.

Application filed June 10, 1919. Serial No. 303,132.

To all whom it may concern:

Be it known that I, Lnwrs FERRY MooDY, a citizen of the United States,residing at Philadelphia, in the county of Philadelphia and 'State ofPennsylvania, have invented certain new and useful Improvements inRotary Pumps with Adjustable Gates, of which the following is aspecification.

' The principal objects of my invention are to provide new and improvedmeans for controlling the performance of a rotary hydraulic pump and toprovide a method of moving Water against an opposing head for which sucha pump may be employed. .Another object of my invention is the maintenance of high efliciency in a rotary hydraulic pump when the pump isoperated at "arious rates of discharge, that is, the improvement of theefficiency of the pump when discharging quantities of water greater orless than the normal or designed quantity. Still another object is theprovision of a regulating or controlling valve for a pump which can beconveniently and quickly op.- erated by means of fluid pressure. Allthese objects and others will be appreciated upon consideration of alimited number of specific examples of practice under my invention whichare disclosed in the fol lowing specification and claims taken with theaccompanying drawings. It will be understood that modifications may bemade within the scope of my invention.

Referring to the drawings,

Figure 1 is a vertical section of a vertical shaft pump embodying myinvention.

Fig. 1 shows a detail of Fig. 1.

Fig. 2 is an axial section of a horizontal shaft pump illustrating adifferent type of pump and gate control means and Fig. 3 is an axialsection of a different type of pump embodying my invention.

. Referring to Fig.1, the power shaft 11 in the bearing '12 and passingthrough the packing box 13 carries the impeller 14 with the vanes 15 andshroud ring 16. The inflow'conduit '32 leads up vertically to theimpeller, which discharges through the diffuser 19 into thespiralchamber 18 ending in the flange 17, which may be attached to anyFsuitable conduit or receiving tank.

he stationary pump frame 33 supports the spiral casing '18 and anannular cylinder 23, of which the outside wall is 20, the inside wall 21and the annular head 22. Within this annular cylinder 23 is acorresponding plunger 24 with the annular head 25 formng the upper faceof the diffuser 19. This plunger 1s shown in Fig. 1 in the positioncorresponding to the operation of the pump at full discharge. Forreduced output of the pump, the plunger 24 may be lowered as will beexplained more in detail presently. The lnner corner of the head 25 isslightly rounded off at 26 to facilitate such a-part gate operation ofthe device.

The plunger 24 is moved by fluid pressure admitted to the cylinder 23through either pipe 29 or 30. Attached to the plunger 24 is' a restoringrod 40, which goes through a yalve chamber 39 (Fig. 1 in the valve casing 41 having the cylindrical liner 42. The valve member 43 has thepistons 44 and 45 adapted to control the valve ports as shown in thedrawing. This valve member 43 extends outside of the valve casing 41 at46, where it rotatably carries hand wheel 51.

held by a key 48 in slots 47 and 49, so that rotation of hand wheel 51adjusts valve 43 relatively to rod 40 and this adjustment is indicatedon scale 58 on extension 57 passing throughsleeve 54 and cap 55 andhaving a tigglt sliding fit in the former by packing 5 The adjustment ofthe gate 24 corresponding to the setting of hand wheel 51 on scale 58will automatically be maintained by the restoring device for example asfollows: Should the gate 24 move down from its adjusted position valvemember 43 will also be moved down admitting pressure from pipe 27 andport 60 to pipe 30 and connecting pipe 29 to exhaust 61, 28 to raise thegate; conversely upward movement of the gate from adjusted position willconnect pipe 29 to the pressure fluid and pipe 30 to the exhaust tolower the gate back to set position. The space below 44 is connectedwith 61 by a passage not shown. The hand wheel '51 also serves tocontrol the gate movements, for instance to close the gate 24 the handwheel 51 will be rotated counterclockwise, thus causing the valve member43 to move up relatively to the rod 40. Such movement will connectpressure pipe 27 with the ports uncovered by valve member 45 and admitthe pressure fluid through the conduit 29 to close the gate. Theconsequent movement of the restoring rod 40 will close the port underthe valve member 45 and the In full gate operation the parts will have.

the adjustment shown in Fig. 1.- The impeller vanes 15 will receive thewater from the inflow conduit 32, drive it with rela-.

tively high velocity into the difluser 19 and thence with reducedvelocity into the spiral collector 18, where the remainder of itsvelocity energy will be converted with as little loss as possible, intostatic head. If it is desired to reduce the quantity of water beingpumped, the plunger will be lowered to a proper degree under the controlof the hand wheel 51.

The embodiment of my invention shown in Fig. 2 differs from that of Fig.1 in that the pump axis is horizontal instead of vertical and the lungerlocationis on the intake-side of tiie impeller instead of on the sideopposite to the intake. The plunger 24 m the Fig. 2 pump is controlledby by draulic pressure supplied through the pipe 27 and regulated by thefour-way valve 31. This valve is shown in Fig. 2 in position to move theplunger 21 to the left by admitting pressure fluid from the pipe 27throu h the pipe 30 to the right end of the cylin or 23. At the sametime that the pressure is ad- 'mitted to the right end, the pipe 29 fromthe other end is connected by the valve 31 to the exhaust conduit 28.When the plunger 24 has been moved to any desired point, an eighth turnof the valve 31 either way will close all the ports and hold that stageof adjustment. To move the plunger 24: to the right the valve 31 will begiven a quarter turn from the position shown in Fig. 1, so as to connectthe pressure pipe 27 to the conduit 29 at the left end of the cylinder23 and also to connect the exhaust conduit 28 with the pipe 30 at theright end of the cylinder 23.

In the embodiment of my invention shown in 3, the lunger gate is on thelower side of the di user.instead of on the upper side as shown inFig. 1. The impeller vanes 15 carry no shroud ring. The direction offlow through the diffuser 19 is not in a common plane, but is conical aswill readily be seen by comparing Fig. 3 with Fig. 1. The plunger 24 hasits inside cylindrical wall on the inner side of the inside cylinderwall 21 so that as the water flows around the corner 26, it is neversharply deflected and no pocket can be formed by the rounded corner 26passing within any part of the casing.

In Fig. 3, the {gate 24 is shown at normal full gate position by thefull lines, but it is designed for operation at overgate adjustment, ifdesired, as indicated by the dotted lines. In this case, there will bean annular clearance space around the outer ends of the impeller vanes15, but the water will be dragged along through this annular clearancespace by the stream nearer the axis which is moved in a more positivemanner by the impeller vanes 15. The action will be somewhat on theprinei 1a of the ejector by which one stream of uid is caused to pick upand impart its motion to another body of fluid. The operation underover-gate conditions as described maybe advantageous when it is desiredto move an unusually large volume of water at some what less than theusual head, and when-the maintenance of'the full normal efliciency ofoperation is not important under such unusual conditions. i i

Itwill be seen that I h'aveprovided a pump in accordance with myinvention,

which will operate to give widely different. discharge rates withoutundue sacrifice 'of efliciency. When the plunger gate is wide open, thewater is delivered from the mar-' gin of the impeller into' the diffuserspace 19 with a considerable velocity energy. When the plunger gate isnearly closed, the impeller forces the water through the comparativelynarrow difi'user with a velocity as high as before, but in diminishedvolume. The Water flows around the rounded corner 26 of the plunger head25 with smooth lines of flow in a manner somewhat similar to the flow ofa jet from an orifice. The diminished output of the pump under part-gateconditions means a corresepondingly dimin-' ished requirement of power,because the re? duced output is obtained without throttling in such away as to set up eddies or otherwise occasion loss of energy.

An advantage of the arrangement of this invention is the provision of awell formed difi'usion space at alldegrees of openin of the plungergate, so that in all positlons there will be ample space for a gradualreduction of velocity and conversion of velocity head into pressurehead. Moreover, as the opening is made smaller, the loss which wouldotherwise be caused by sudden enlargement at the outer periphery of theplunger is offset by the relatively greater efliciency of difi'usion dueto the *greater ratio of length to' width of the difi'usion space. Forwhen the plunger is partially closed, the length of passage traversed bythe water is much greater in proportion to its width than when theplunger is open, and the conversion of velocity head into pressure headwill be more efliciently effected in the part-gate position. Thereforein.

the outer periphery of the plunger, which s the outer periphery of thediifuser, and

enters the spiral casing, its velocity is greatly reduced both in itsradial and Whirl components. Thus under conditions of reduced dischargethe loss due to the casing being too large in cross section to suit theWhirl component Will be largely overcome by the conversion of Whirlcomponent w1thin the difi'usion space.

Another advantage of my invention the simplicity and ruggedness of thestructure, 10 especially as compared with wicket gates or adjustableguide vanes, which lnvolve considerable mechanism and are notpracticable for providing an adjustable diffusion space.

I claim 1. In a rotary pump, an impeller, a diffuser around saidimpeller with substan tially parallel annular Walls, and a conduitaround said difl'user, one of said walls of the diffuser being movableto or from the other and relatively to the adjacent edge of thedischarge space of said impeller to adjust the capacity of the pump.

2. In a rotary pump a rotary impeller,

a plunger gate surrounding said impeller and displaceable axially withrelation to the edge of the discharge space of said impeller to adjustthe capacity of the pump and means to move said gate by fluid pressure.

3. In a rotary pump, a plunger gate displaceable axially to adjust thecapacity of the pump, a cylinder and coacting piston, one fixed and theother connected with said gate, and means at each end-of said cylinderto introduce fluid pressure between said piston and the correspondinghead of the cylinder to move said gate in either direction.

4:. In a rotary, pump, an impeller having passages of constantcross-section, and a gate close to and coaxial with theimpeller butseparate therefrom and movable axially to adjust the cross section atsaid gate of the stream through the pump.

5. In a rotary pump, an impeller having passages of constantcross-section, a diffuser adjacent thereto, and means to adjust thedifi'user by varying its cross section across the lines of flow, therebyto adjust the capacity of the pump.

6. In a rotary pump, an impeller, and a coaxial gate closely adjacent tothe impeller and adapted to be moved relatively to the adjacent edge ofthe discharge space of said impeller.

7. The method of adjusting the capacity of a rotary pump having adifluser and impeller which consists in varying the cross section of thediffuser across the lines of flow therethrough While maintaining thecross section of the passages Within the impeller unchanged.

8. The method of adjusting the capacity of a rotary pump which consistsin cutting ofi' to a'suitable degree the cross section of the streamacross the flow lines, at points close to the impeller on its deliveryside without changing the cross sectional area of the passages Withinthe impeller.

9. In a rotary pump, an impeller having passages of constant axialWidth, a difi'user adjac'ent' thereto, and means to vary the axial Widthof the diffuser to adjust its cross section across the lines of flow,thereby to adjust the capacity of the pump.

10. In a rotary pump, an impeller, and a coaxial gate closely adjacentto the impeller and displaceable in an axial direction relatively to theadjacent edge of the discharge space of said impeller to adjust thecapacity of the pump.

11. The method of adjusting the capacity of a rotary pump having animpeller and a diffuser which consists in varying the cross section ofthe difluser across the lines of flow therethrough without changing thecross section of the passages Within the impeller.

12. The method of adjusting the output of a rotary pump having adiffuser Withoutsacrifice of efliciency Which consists in varying thecapacity of the diffuser by relative movement of its guiding surfacesWithout changing the cross sectional area of the passages within theimpeller.

13. The method of adjusting the capacity of a rotary pump having anannular outward flow diffuser surrounding the impeller which consists invarying the width of the diffuser in an axial direction without changingthe cross sectional area of the passages within the impeller.

14. In a rotary pump, an impeller, a diffuser around said impeller withsubstantially parallel annular walls and a spiral conduit around saiddiffuser, one of said Walls of the difl'user being movable to or fromthe other and relatively to the adjacent edge of the discharge space ofsaid impeller to adjust the capacity of the pump. 15. In a rotary pump,an impeller, a diffuser around said impeller with substantially parallelannular walls, and a conduit around said diffuser, one of said walls ofthe, diffuser being movable to or from the other and relatively to theadjacent edge of the discharge space of said impeller to adjust thecapacity of the pump, said movable wall having its edge toward theimpeller rounded off to give smooth lines of flow around it.

16. In a rotary pump, an impeller, a diffuser around said impeller, anannular cylinder adjacent .to said difluser, and a corresponding pistontherein, one Wall of said difiuser being connected to said piston by acylindrical barrel.

17. In a rotary pump, an impeller, a diffuser around said impeller, anannular cylall inder adjacent to said diflfuser, a correspending pistontherein, one wall of said difluser being carried by said piston,pressure supplyconduits to the ends of said cylinder, and valve means tomove said piston either way or hold it at any desired adjustmententirely by the admission of fi-uid pressure to either side ofgthepiston.

18. In a rotary pump,- an impeller, a diffuser, around said impeller, anannular cylinder gate moved by fluid-pressure adjacent to said'difi'user, a corresponding piston therein, one wall of said diffuserbeing carried by said piston, pressure supply conduits to the ends ofsaid cylinder, and valve means to move said cylinder either way and toautomatically maintain it at any,

desired adjustment or restore it if displaced.

19. In a pump the combination with guidin walls forming a passagedirecting the flow of fluid, of impeller vanes extending of fluid,-ofimpeller vanes extending only partly across said passage, said wallsbeing formed to cause the flow through the remainder ofthe passage to'bedrawnalong by the vanesand said gate being movable to direct,substantially all of the fluid 'throu h saidvanes.

21. n a pump the combination withan impeller and inlet and dischargepassages, of a plunger gate in said discharge adjustable relatively tothe adjacent edge of the discharge space of said impeller and'havinganormal position for full load, said parts being formed to permit saidgate to be moved! to giveeither greater or less discharge than that forsaid normal position.

22. In arotary pump, an impeller, a diffuser around said 1mpeller,'-anannular cylinder adjacent to said difi'user, a corresponding pistontherein, one wall of said difluser being carried by said piston,pressure supply conduits to the 'ends of said cylinder, and valvemeansto move said cylinder either way and to automatically maintain itat any desired adjustment or restore it if displaced.

23. The method of regulating the capacity of a rotary pump having animpeller and a discharge opening therefrom, com-" prising varying thecross section of said discharge opening adjacent said impeller withrelation to the cross section of the passages of said impeller.

LEWIS FERRY MOODY.

